False teeth, plate, mold, and method of making



-April 9, 1929. J. 5. DONNELLAN 1,708,665 FALSE TEETH; PLATE, MOLD, ANDMETHOD OF MAKING Filed on. 1, 1927 56 avg-5,5? 71ml] $442M W YZJZW Zg A?Patented Apr. 9, 192.9. 1 i i v i usiran stares rarest orrica.

JAMES S. DONNELLAN, OF LOS ANGELES, CALIFORNIA, ASSIGNOR OF ONE-HALF TOJAMES R. SHAW, OF LOS ANGELES, CALIFORNIA. 7

FALSE TEETEI, PLATE, MQLP, AND METHDLD OF MAKING.

Application filed October 1, 1927. Serial No. 223,318.

,My invention is in the construction of false manner desired inv thefinished teeth. This teeth, the plates for such teeth,'the molds forforms impressions in the plaster of Paris making the plates and themethod of making which is allowed to harden before removal such molds.from the mouth. The molds with the plaster An object of my invention isthe construcof Paris then exhibit the configuration of tion ofaspecialmold which may be used with both the lower and upper gum structures ahardening material, such as plaster of and the parts of the mouthadjacent thereto. Paris, to obtain a cast of a persons mouth, Should ithappen that the wax molds previsuch as the gums,oto form plates in whichously made are not sufficiently accurate, either 1 false teeth are set.in addition, my invenbeing considerably too large or too small. an tioncomprises the mannerof usingthe molds other set of wax molds is madewith the to obtain the impression of the mouth and teeth fitted therein,this being a more close gums, and in modeling the molds from thisapproximation to the shape of the patients cast and obtaining'furthercasts until a satisgums, as illustrated by the plaster casts whichfactory cast is developed. have been taken. These new molds may be Afurther object of my invention. is the for both the upper and lowerteeth, or merely construction of'plates for false teeth, especialone orthe other. 1y for the lower jaw, in which such plate in- Y if new moldsare necessary, these are fitted terloclrs in a dovetail manner'with theformain the. patients month, using the plaster of 20 tion of the lowerstructure of the gums of Paris or equivalent composition to obtain thethe lower jaw. V impression of the upper and lower gums, In connectionwith my invention I utilize through the patient placing the molds in themolds-for the upper and lower teeth. For mouth and biting the teethtogether. After the upper teeth 1 form a mold whie. maybe an impressionis obtained in a mold, which 25 made of wax with a wire re-enforcingtherein is sufliciently similar to the plates desired having the teethset in the mold; or, I may for the finished teeth, these are used inmakuse a metal plate,such as aluminum, with wax ing hard rubber or otherplates in the manner molded on the plate and upper teeth set in known inthe trade, by casting operations, the wax. This plate or the wax moldhas a having-the teeth molded therein.

39 bridge adapted to fit against the roof of the My invention in itsseveral aspects will be so, mouth. The mold for the lower teeth isprefmore readily understood from the following erably made of waxwithsuitable wire redescription and drawings, in which: enforcing, andwithv the teeth secured in the Figure 1 is a perspective View of a moldwax, and the mold has a pair of depending having the upper teethincorporated therein lugs adapted to iit inside of the lower gum toobtain a cast of the upper part of the 35 structure. These lugs may becurved slightly mouth. outwardly to fit inside the gum structure, be-Fig. 2 is a longitudinal section on the line ing as close a fit may beestimated by the 2 of Fig. 1, illustrating in addition a operator inbuilding the wax mold. plaster of Paris impression therein. 40 The moldfor the lower teeth is preferably Fig. 8 is a view similar to Fig. 2 ofa niodino fitted first. In this case soft plaster of Paris, ficationshowing the mold formed of wax with or other suitable hardeningcomposition. is a re-enforcing. plaeed'in the lower part of the mold,and this Fig. 4 is a perspective view of the mold for is fitted in themouth, the plaster of Paris the'lower teeth with the teeth incorporated45 conforming to the shape of the inside of the therein viewedfronrunderneath. 9; .lower gum structure. The mold for the upper Fig. 5is a cross-section approximately on teeth has a plaster of Pariscomposition the line 5-5 of Fig. 4.- in the direction of the placedtherein and this is fitted in the persons arrows. I mouth. The patientthen bites, pressing the Fig. 6 is a longitudinal section through 59upper and lower teeth togetherin the exact the two molds when placedtogether in the i looking or the gum structure.

"lates the outside part of the per jaw {the upper teeth 23 each side,

' depending rim 35 on each procedure being as follows:

osition of a'person making the plaster of aris impression by biting theteeth together. Fig. 7 is a cross-section of the lower finished falseteeth, illustrating the manner of interdovetail underneath and inside ofReferring to the mold of Figs. '1, and 2, this is designated as theupper toot-h moldll and has a bridging plate 12 which, asshown in Fig.2, is formed bridge, this having a more or less vertical part 15simulating somewhat in shape the outside of the gums of the upper jaw,and having an internal section-'16 pressing the baclrof the teeth 17 tothe bridge plate 12 In the construction shown in Fig. 3, the

bridge plate 20 is formed of'wax'and has a bedded; This base has' asubstantially flat. at the front which flat sur under surface 33 a facecontinues substantially to the rear 34 at of the base converging towardsthe" back or molar teeth. There is a slight downwardly outside edge,beglnn'ing about half way back on the'sides and continuing to'the rearof the mold. 7 There is also a downwardly extending flange 36 on eachside of the inside of the mold, this,hav ing a concave curve'outwardlyand downwardly. These flanges are at their greatest depth at about themid position of the sides, and are of considerable depth compared withthe width of each side of the mold. It is pref-' erable to make the moldfor the lower teeth of wax with a re-enforcing wire 37 or the like.

' In making'the mold for the lower jaw the operator, having matched theteeth which are to form the upper and lower set, makes the mold to-ashape which be estimates will fit comfortablyinthe patients mouth. Theflanges 36 may be turned outwardly at the lower edge to a considerableextent, but'this isnot necessary. After both the molds have been made,they may be fitted .in the mouth either by the operator or by thepatient, the It is preferable to insert the lower, jaw mold in the mouthfirst, and in doing this the-mold is inverted and a plaster of Pariscomposition 40 is placed in this mold, the composition fitting on thesomewhat flatsurface 30, as indicated at 41,and extendingaround thesides, as indiof metal and'has an 'up--v turned flange 13 aroundthe twosides and the front. A wax form 14;: is built-onto the metal I dicate'din Fig. 2,

the top of the teeth and the bottom for a hard rubber cated at 42, alsoextending towards therear 34, there being a considerable layer on theoutside of the flanges 36. This need not be molded to shape but should"be. sufficiently pressed so that when inserted in the mouth it will holdthe shape. Y

The patient inserts the mold in the mouth by first fitting the flange onone side so as to curve underneath the so'lid'part of the jaw formingthe gums, centered inthe desired position in the mouth.

1 The upper mold-is then used and has a plaster of Paris compositiondesignated gen erally by the numeral 43. This is placed to aconsiderable depth in the front part," as infitting against the flange13 or 22, in accordance withwhet-her a metal bridge plate flange is used'or an all wax'mold.

his composition extends rearwardlyon the bridge, as indicated at 45,being of sufficient depth to formanimpression. This moldis thenifisertechfitting in the upper jaw with the bridge adjacent the'roof ofthe mouth and pressing the gums well into the plaster of Paris on'thebridge and against the flanges. The upper and lower teeth are brought tothe desired position that they should occupy in use, then thepatientbites, pressing the teeth firmly together, which action embedsthe gums andthe flesh covering the bony structure of the upper and lowerjaws into the plaster of Paris compositionand causes this to flowfilling all the void spaces and conforming to the shape of the gums andsuch fleshy structure of the upper and lower jaws.

If, on inspection of the impressions taken in the molds, .the operatoris ofthe'opinion that it is desirable tomake a new set of molds, theseare made, setting the teeth in the nosition indicated as'beingapproximately correct as shown by the impression of the gums and formingcomplete new molds. 1 Ere-- 'quently the plaster cast can be removed andthe operator can rework the molds already constructed into anapproximate shape. Should thisbe done the iiatient makes an impressionin the manner above describer, using plaster of'Parisor tion. I lVhenasatisfactory cast has been obtained showing the impression of the gums,this impression on the wax mold or the wax mold with the metal bridge isused to form a mold or other similar composiion plate, in which thefalse teeth are to be embedded, the wax being melted andallowcd toflowout of the mold and the-plaster of Paris core being removed. Thefalse teeth withthe plate thereon for the upper set do not departradically from false teeth and plates as now constructed as a-finishedarticle, but-the manner of procedure to arrive at thecorrect shape isdifferent from the present art.

In the false teethand plate for the lower and then this is properlysimilar composieinbeddechtheoutside portion 53 simulating the outerpartof the gums which are visible. The plate has a lower surface 54which is sub stantially parallel to the upper edges of the teeth exceptthat this surface draws upwardly towards/the top of the molar teeth inthe same manner as the mold, as indicated in Fig.

i. There are opposite rims 5.5 which extend downwardly slightly on theopposite sides about midway back of the tooth structure.

The heavy flanges 56 have a decided outward projection 57 at the bottom,these being on each side at the place indicated by the flanges 36 in themold of Figs. 4 and 5. This leaves concave pockets 58 on opposite sidesof the flanges of the plate. The inner surface 59 of the flanges has aconvex curve and is sufliciently cut away to accommodate the personstongue In fitting the completed false teeth with their plate in thelower jaw, one side is pressed into position under the flesh of the bonystructure forming the gum. The plate is pressed towards the rear and theother side is slipped into position and the plate with the teeth ispulled forwardly. This causes the lateral extensions 57 of the flanges56 to fit partly underneath this bony structure, and such structure fitsin the pockets 58 in a species of dovetail connection; The false teethwith the plate are, therefore, firmly locked into position, and whenproperly fitted they are held in such firm relation 'to the lower jawthat it is somewhat difficult for the wearer to remove the teeth. Theupper aw set of teeth fit in the usual manner, and if the manipulationofthe molds has been correct, the teeth will fit in the manner indicatedthey should fitin taking the impressions and forming the last mold.

A characteristic feature of my invention is that the wax mold for theupper teeth and the 10 er teeth is of a very strong construction, theupper mold having in one case either a metal bridge or a wirere-enforcement, and the lower mold having a wire re-enforcement.Therefore, after the impression of the gums has been made in plaster ofParis and this has hardened, the person into whose mouth the molds arefitted may use the teeth to bite hard substances such as crusts ofbread, masticating these to see if a proper fit for proper masticationof the food has been obtained. This is a decided advantage of my moldsover those as constructed in accordance with the prior art.

An important feature of the mold for the lower teeth is the constructionhaving the depending flanges 36 which extend downwardly fromsubstantially a horizontal surface and on the inside of the U-shapedstructure at the rear portion thereof. When the lower surface of themold and the outside surface of these flanges are covered with theplastic composition and the mold fitted in the mouth, the patient bitingon the teeth, the plastic composition is shaped somewhat as shown inFig. 5. This has the outward bulges at the bottom conforming to theflesh and bony structure of the lower part of the jaw. Therefore, in

the finished false tooth mounting as shown in Fig. 7 the pockets 58allow the fitting of the bone and fleshy structure of the lower part ofthe jaw therein. This causes the lower set of teeth to lock in the jawand the harder a person-bites the tighter they look therein. Thisconstruction prevents rocking of the lower set of teeth.

Various changes may be made in the principles of my invention withoutdeparting from the spirit thereof, as set forth in the description,drawings and claims.

I claim:

1. The method of making dental impressions comprising inserting a lowertooth mold in the mouth with the mold resting on the lower gumstructure, the mold having a plastic composition on depending'fiangesadj acent the back and on the under surface and bitin on an upper set ofteeth, the lower mold forming an impression by squeezing the plasticmaterial partly underneath the bony structure of the lower gums from theinside towards the outside.

2. In the method of making. a dental impression of the lower gums,placing a mold having downwardly extending flanges adjacent the backwith a plastic material on the outside of the flanges in the mouth,resting on the lower gums and biting against such mold, thereby forcingthe impression-receiving material outwardly and underneath the bonystructure of the lower gums.

3. A set of false teeth for the lower jaw having a supporting structurewith depending flanges adjacent the back extending downwardly on theinside, said flanges having outwardly projecting extensions fittingunderneath the bony structure of the lower gums from the inside.

4:. A set of false teeth for the lower jaw comprising teeth embedded inthe supporting material, the supporting material being substantiallyU-shaped in plan and having a substantially fiat under surface to fit ontop of the gums and a pair of downwardly extending flanges on theinside, said flanges adjacent the back having outwardly extendingportions adapted to form lateral pockets, said lateral pocketsaccommodating the flesh and bony structure ofthe lower gums on theinside thereof.

5. A set of false teeth for the lower jaw, comprising a supportingstructure with teeth smbedclecltlieiein, this being substantially U- Vshaped in plan and having-a substantially flat undelf'surfaee v to fitOn top of the gums; a pair of downwardly depending flanges at thebackand on the'insicle of the U ,said flanges having outwardly extendingportions at the bot-tom adapted to form lateral pockets, said lateralpockets accommodating vthe flesh and bony structure of the lower gumson'*the' inside thereof. l

In testimony whereof I have name to this specification. l

s. DONNELLAN.

signed my

